AK4250VU - Asahi Kasei Microsystems Co., Ltd. (AKM)

[AK4250]

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GENERAL DESCRIPTION

The AK4250 is a Video Amp with LPF. The output coupling capacitor can be removed because the

AK4250 includes the negative power supply circuit. The AK4250 is housed in a space-saving 8-pin

USON or 8-pin TMSOP package.

FEATURE

1. Video Function

• A Composite Video Input

• A Video-Amp (+6dB) for Composite Video Signal

• Low Pass Filter

• Charge pump circuit for negative pow er supply

2. Ta = -40 ∼ 85 °C

3. Power Supply: 2.7 ∼ 3.6V (typ. 3.0V)

4. Power Supply Current: 10 mA

5. Package: 8 pin USON (AK4250VU)

8 pin TMSOP (AK4250VT)

■ Block Diagram

VIN Clamp LPF VOUT

VDD Charge

Pump

Clock

Generator

PDN

CP CN VSS VEE

Figure 1. AK4250 Block Diagram

AK4250

Output Coupling Capacitor-less Video Amp with LPF

[AK4250]

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■ Ordering Guide

AK4250VU −40 ∼ +85°C 8 pin USON (0.5mm pitch)

AK4250VT −40 ∼ +85°C 8 pin TMSOP

AKD4250 Evaluation board for AK4250

■ Pin Layout

AK4250VU

VDD Top

View

VIN

PDN VOUT

VSS

VEE

AK4250VT

Top View

VDD

VIN

PDN

VEE

VSS

VOUT

[AK4250]

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PIN/FUNCTION

No. Pin Name I/O Function

1 CP O

Positive Charge Pump Capacitor Terminal Pin

2 VDD - Power Supply Pin.

3 VIN I Composite Video Signal Input Pin

4 PDN I Power-Down Mode Pin. Internal Pull Down 100kΩ.

“H”: Power up, “L”: Power down.

5 VOUT O Composite Video Signal Driver Pin

6 VSS - Ground Pin

7 VEE O Negative Voltage Output Pin for Video Amplifier

8 CN I

Negative Charge Pump Capacitor Terminal Pin

ABSOLUTE MAXIMUM RATINGS

(VSS=0V; Note 1)

Parameter Symbol min max Units

Power Supplies: VDD −0.3 4.0 V

Input Current, Any Pin Except Supplies IIN - ±10 mA

Input Voltage (Note 2) VIN −0.3 (VDD+0.3) or 4.0 V

Ambient Temperature (powered applied) Ta −40 85 °C

Storage Temperature Tstg −65 150 °C

Note 1. All voltages are with respect to ground.

Note 2. VIN, PDIN pins. Max is smaller value between (VDD+0.3)V and 4.0V

VOUT pin becomes Hi-Z at the PDN pin = “L”. Therefore the VOUT pin is available to signal line from another

device by Wired-OR. The input signal to the VOUT pin must not exceed this input voltage range.

Any voltage must not be applied to the CN pin.

WARNING: Operation at or beyond these limits may result in permanent damage to the device.

Normal operation is not guaranteed at these extremes.

RECOMMENDED OPERATING CONDITIONS

(VSS=0V; Note 1)

Parameter Symbol min typ max Units

Power Supplies VDD 2.7 3.0 3.6 V

Note 1. All voltages with respect to ground.

* AKM assumes no responsibility for the usage beyond the conditions in this datasheet.

[AK4250]

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ANALOG CHRACTERISTICS

(Ta=25°C; VDD =3.0V; VSS = 0V; unless otherwise specified)

Parameter Conditions min typ max Units

V Input Characteristics

Input Voltage - - 1.5 Vpp

Input Sync Chip Clamp Voltage (Note 3) -0.386 -0.286 -0.186 V

V Output Characteristics (Note 4)

Output Gain VIN=100kHz, 0.2Vpp 5.0 6.0 7.0 dB

Maximum output voltage VIN=100kHz , THD=-30dB 2.52 - - Vpp

S/N BW=100kH ∼ 6MHz, (Note 5) - 65 - dB

Secondary Distortion VIN=3.58MHz, 0.2Vpp (Sin Wave) - -45 - dB

Load Resistance 140 150 - Ω

Load Capacitance C1 (Figure 2)

C2 (Figure 2)

400

LPF

Frequency Response Response at 6.75MHz -3 -0.5 - dB

Input= 0.2Vpp, Sin Wave Response at 27MHz - -40 -20 dB

(0dB at 100kHz)

Group Delay |GD3MHz - GD6MHz| - 10 100 nsec

Power Supplies

Power Up Black signal is output and no load

resistance.

- 10 15 mA

Power Down PDN pin = 0V - 1 2 μA

Note 3. The Charge Pump circuit will not work well, if the sync chip clamp voltage input to the VIN pin is not within this

voltage range. This sync chip clamp voltage is the voltage from the pedestal voltage

Note 4. The measurement point is the point A in Figure 2

Note 5. The reference signal is the 100% white signal.

Video Signal Output 75 ohm

75 ohm

R1 R2

Measurement Point A

Figure 2. Load Capacitance C1 and C2

DC CHRACTERISTICS

(Ta=25°C; VDD=2.7 ∼ 3.6V)

Parameter Symbol min typ max Units

High-Level Input Voltage (PDN pin)

Low-Level Input Voltage (PDN pin)

VIH

VIL

1.5

0.6

[AK4250]

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■ Video Block

The Video Amp has a drivability for a load resistance of 150Ω. The AK4250 has a composite input and output and

includes a low pass filter (LPF). Internal negative power supply circuit supplies negative voltage to the video amp and

video amp 0V output is used for a pedestal level. Therefore, the output coupling capacitor can be removed.

VDD Charge

Pump

CP CN VSS VEE

1uF

Negative Power

K4250

(+) C2

C1 (+)

Note 6. C1 and C2 capacitors should have the low ESR (Equivalent Series Resistance) over all temperature range.

When these capacitors have the polarity, the positive polarity pin should be connected to the CP pin and the VSS

pin. Non polarity capacitors can also be used.

Figure 3. Negative Power Supply circuit

VOUT

K4250

75Ω

Figure 4. Video signal output

■ Power Down Control

When the PDN pin is “L”, the AK4250 is forced to the Power Down Mode (Power consumption: typ 1μA). The VOUT

pin becomes Hi-Z at the PDN pin = “L”. The AK4250 includes a power-on-reset function. Therefore any reset is not

required externally.

[AK4250]

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SYSTEM DESIGN

Figure 5 shows the system connection diagram for the AK4250. An evaluation board [AKD4250] is available which

demonstrates the optimum layout, power supply arrangements and measurement results.

Top View

Power Supply

2.7∼3.6V

DSP or μP

10µ VDD2

VIN

PDN

0.1u

VEE

VSS

VOUT

1µ

0.1µ 1µ

(+)

Figure 5. Typical Connection Diagram

Note:

- Any voltage must not be applied to the CN pin.

[AK4250]

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PACKAGE (AK4250VU)

8pin USON (Unit: mm)

2.2 ± 0.05

0.05

0.6MAX

1.2 ± 0.05

1.9 ± 0.05

0.25 ± 0.05

0.5 0.2 ± 0.05 0.05 M

We recommend mounting this portion onto circuit

oard in order to secure mounting intensity. Please do

not connect to a Power Supply, GND, Signal Line, etc.

■ Material & Lead finish

Package molding compound: Epoxy

Lead frame material: Ni

Lead frame surface treatment: Au plate

[AK4250]

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PACKAGE (AK4250VT)

8pin TMSOP (Unit: mm)

M0.1

4.0±0.2

2.8

2.9+0.12

-0.1

0.65

0.127+0.1

-0.05

0.55±0.2

0~10°

0.95 max.

0.1 +0.1

-0.05

0.1

0.2±0.05

■ Material & Lead finish

Package molding compound: Epoxy

Lead frame material: Cu

Lead frame surface treatment: Sn-Bi (Pb free)

[AK4250]

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MARKING (AK4250VU)

250

XXX: Date code (3 digit)

MARKING (AK4250VT)

(1) #1Pin Indicator

(2) Chip No. (AK4xxx=xxx)

(3) Year 1 Digit

(4) Month 1 Digit

(5) M anage Code (Interna l use)

(3) (4) (5)

(1)

7 6 5

1 2 3 4

Y 5 0

(2)

[AK4250]

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REVISION HISTORY

Date (YY/MM/DD) Revision Reason Page Contents

07/03/28 00 First Edition

07/11/05 01 Spec Change 4 Power supply current consumption at power down

max 20μA → 2μA

08/09/05 02 Error Correct 8 Marking was changed.

10/04/08 03 Error Correct 7 ■ Material & Lead finish

Lead frame surface treatment: Ag plate → Au plate

10/06/07 04 Description

Addition

The AK4250VT was added.

IMPORTANT NOTICE

z These products and their specifications are subject to change without notice.

When you consider any use or application of these products, please make inquiries the sales office of Asahi Kasei

Microdevices Corporation (AKM) or authorized distributors as to current status of the products.

z Descriptions of external circuits, application circuits, software and other related information contained in this

document are provided only to illustrate the operation and application examples of the semiconductor products. You

are fully responsible for the incorporation of these external circuits, application circuits, software and other related

information in the design of your equipments. AKM assumes no responsibility for any losses incurred by you or third

parties arising from the use of these information herein. AKM assumes no liability for infringement of any patent,

intellectual property, or other rights in the application or use of such information contained herein.

z Any export of these products, or devices or systems containing them, may require an export license or other official

approval under the law and regulations of the country of export pertaining to customs and tariffs, currency exchange,

or strategic materials.

z AKM products are neither intended nor authorized for use as critical componentsNote1) in any safety, life support, or

other hazard related device or systemNote2), and AKM assumes no responsibility for such use, except for the use

approved with the express written consent by Representative Director of AKM. As used here:

Note1) A critical component is one whose failure to function or perform may reasonably be expected to result,

whether directly or indirectly, in the loss of the safety or effectiveness of the device or system containing it, and

which must therefore meet very high standards of performance and reliability.

Note2) A hazard related device or system is one designed or intended for life support or maintenance of safety

or for applications in medicine, aerospace, nuclear energy, or other fields, in which its failure to function or

perform may reasonably be expected to result in loss of life or in significant injury or damage to person or

property.

z It is the responsibility of the buyer or distributor of AKM products, who distributes, disposes of, or otherwise places

the product with a third party, to notify such third party in advance of the above content and conditions, and the buyer

or distributor agrees to assume any and all responsibility and liability for and hold AKM harmless from any and all

claims arising from the use of said product in the absence of such notification.